There is a hidden gem for emulators: VIXEN357 which is actually an top-down RPG with mechas. Cons: but it comes without vixens and without .357 guns.
We need to go deeper: there's a site to play DOS games right in a browser:
https://www.playdosgames.com/online/zone-66/
https://www.playdosgames.com/online/zone-66/
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